The present invention relates generally to satellites, and more particularly, to a low cost, injection molded phased array antenna system that may advantageously be used on satellites.
In addition to lower costs and shorter delivery schedules, the current trend in synchronous orbit satellites and satellite antennas is to provide more power and more payload capability, including more independent antenna beams. Satellite antennas while meeting other requirements must be low cost, quickly produced and mount to available spacecraft mounting locations. Also, the spacecraft with antennas and solar arrays must fit within the shroud of the launch vehicle. Spacecraft mounting space and shroud volume are limited, and larger launch vehicles with larger shrouds are costly.
Transmit and receive functions are often separated into two antennas, each covering a narrow bandwidth, resulting in a reduction in transmit feed system losses and an improvement in antenna beam shape optimization efficiency. Improved transmit antenna performance reduces the high costs associated with supplying more solar array DC power, traveling wave tube amplifier (TWTA) RF power, and thermal control.
A deployed shaped-reflector antenna is frequently used to satisfy transmit requirements and an earth facing, deck-mounted reflector antenna is used to satisfy receive functions. An earth deck structure is necessary to hold the receive antenna reflector, subreflector and RF feed. At Ku-band, the projected aperture of the earth deck antenna diameter is typically 1.2 meters. The reflector, subreflector and structure are made of graphite composite materials.
It would therefore be advantageous to have an improved phased array antenna system which may be used on satellites that improves upon conventional antennas.